ES2464642A2 - PESTICIDE WITH INSECTICIDE, ACARICIDE AND NEMATICIATED ACTION BASED ON ISOQUINOLINIC ALCALOIDS AND FLAVONOIDS - Google Patents

Abstract

The present invention relates to a pesticide with insecticidal, acaricidal and nematicidal action, obtained from plant extracts that have important synergistic interactions in their pesticidal activity, whose main characteristics are: an efficient control for insects, mites and nematodes; Low toxicity for mammals and low persistence in the environment. This pesticide consists of a composition based on plant extracts, which is characterized by being: Isoquinoline alkaloids and their derivatives 0.1 - 20% Flavonoids and their glycosylated derivatives 0.001 - 10% Therefore, the scope of the invention is closely adjusted general to organic pesticides and in particular to obtaining an organic pesticide containing as active ingredients a mixture of isoquinoline alkaloids and flavonoids for their use for the control of agricultural pests.

Description

SCOPE OF THE INVENTION

An invention is presented consisting of a pesticide with insecticidal, acaricidal and nematicidal action that contains at least one isoquinoline alkaloid and at least one flavonoid, and that have important synergistic interactions in its biological activity, efficient for pest control and whose main characteristics are : high specificity on white pests, low toxicity for mammals, low persistence in the environment and where the active ingredients could come, although not exclusively, from plant extracts.

Likewise, a manufacturing procedure is described, consisting of two stages, where the first stage refers to obtaining and standardizing the active principles of the pesticide: isoquinoline alkaloids and flavonoids, as well as a second stage related to its commercial formulation.

OBJECTIVES OF THE INVENTION

The present invention is related in general to the biorational use of pesticides of botanical origin for the integrated management of pests and in particular to the use of plant extracts, which contain mainly isoquinoline alkaloids and flavonoids as active secondary metabolites.

Therefore, the main objective of the present invention is the use of plant extracts for the integrated management of pests, so it does not imply risks for the environment, since they are biodegradable substances that, in general, persist little time in the environment and therefore they do not contaminate and provide a biorational alternative to the use of conventional chemical pesticides.

It is an objective of the present invention that the mixture of plant extracts and their chemical composition allows it to exert its pesticidal activity on insects, mites and nematodes, via different mechanisms of action.

its formulation, are constituted by a set of active principles, chemically distinct from each other. This decreases the likelihood of resistance development by target organisms.

It is another objective of the present invention to provide a pesticide with a combination of ingredients with synergistic properties, which allows reducing the amount of active ingredients without affecting the biological effectiveness against pest organisms, allowing it to present a low toxicity for mammals.

BACKGROUND OF THE INVENTION

Historically, the first generation of pesticidal plant molecules dates back to the 19th century, where some compounds of plant origin such as alkaloids, rotenone and rotenoid compounds, pyrethrins and essential oils were identified.

Alkaloids are secondary nitrogen metabolites, usually of a basic nature and most of these compounds are biosynthesized from amino acids. Nicotine is an alkaloid isolated from the tobacco plant, mainly from Nicotiana tabacum and Nicotiana rustica (Solanaceae), and is considered a toxic and dangerous pesticide for humans. It is a neurotoxin that acts specifically on nicotinic cholinergic receptors, delaying the closure of sodium channels, causing paralysis before death.

Sabadilla is a pesticide obtained from the seeds of Schoenocaulon officinale. Its active ingredients are mainly cevadine and veratridine alkaloids which are esters of a steroidal alkaloid called veracevine and are toxic to mammals (DL5 or 13 mg / kg), but in commercial preparations containing it as an active ingredient its concentration is less than 1 %. The mechanism of pesticide action of this type of alkaloid is similar to that of pyrethrins.

Ryania is a wood powder from Ryania speciosa and its activity is attributed to ryanodine «1%), a pyrrole-2-carboxylic ester of a complex diterpene (ryanodol). Ryanodine exerts its pesticide activity interfering with the release of calcium in muscle tissue causing sustained muscle contraction that may be accompanied by paralysis.

Rhizomes of tropical legumes Derris, Lonchocarpus and Tephrosia. Most of the rotenone currently used comes from Lonchocarpus, also known as cube root. Oe this root is extracted approximately 44% rotenone and 22% deguelin, another rotenoid. Rotenone is a mitochondrial poison, which blocks the transport of electrons and prevents energy production. Rotenone is toxic to humans (OL5 or 132 mg / kg) and although commercial formulations are used at less toxic levels of lethal doses, this pesticide has limited use in agriculture.

The pyrethrum is extracted from the flowers of the chrysanthemum Tanacetum cinerarifolium (Asteraceae) and is a mixture of 6 secondary metabolites: pyrethrins I and 11, the cinerines I and II and the jasmolines I and 11. The pyrethrum is a neurotoxin that causes immediate paralysis In insects, since it blocks the sodium-dependent voltage channels in the axons, this mechanism of action is similar to that of the organochlorine pesticide OOT, but unlike this, pyrethrins show moderate toxicity towards mammals. Despite its immediate action, most insects recover, unless the pyrethrum is formulated with a synergistic agent. The pyrethrum constitutes approximately 80% of the total commercial botanical biopesticides worldwide.

Essential oils are the volatile aromatic principles of plants, of a complex chemical nature that mainly include terpenoids, with monoterpenes being the majority compounds and to a lesser extent sesquiterpenes (which contain 10 and 15 carbon atoms, respectively) and more rarely diterpenes (20 carbon atoms). Essential oils, mainly monoterpenes, are specifically toxic against insect pests, due to their neurotoxic mechanism, which acts on octopaminergic receptors in the nerve impulse transmission system of invertebrates. Essential oils due to their volatile nature are likely to enter the insect through their respiratory system and are currently used primarily to protect domestic animals and clothing (against moths), as well as wood preservatives.

Phytosanitary products of plant origin of this first generation were replaced by pesticides product of chemical synthesis such as organochlorine compounds, organophosphorus and carbamates, which caused strong problems of pollution to the environment and resistance of insects, in addition to harmful effects to Non white organisms. In response to all these problems, a purely chemical strategy emerged that sought to modify the structures of natural products to obtain compounds with a better pesticide activity and less toxicity to mammals, giving rise to pyrethroids. The interest in the development of products of plant origin was also renewed in an important way, and chemical ecology arose, where chemists, biochemists, toxicologists and specialists in plant protection joined forces in the investigation of natural products of botanical origin for the control of pests with a minimum of environmental problems, which gave the pattern to the second generation of botanical pesticides.

The more detailed study of insect plant relationships, allowed us to know that evolution has provided plants with chemical mediators involved in the communication between species, known as semiochemical compounds, which are considered non-nutritive compounds produced by an organism that affect behavior or the biology of individuals of the same species (pheromones) or of different species (allelochemical molecules), the latter have a series of effects against harmful insects, and are classified according to their mode of action in defensive, toxic, repellent or deterrent substances , antipyostimulants or inhibitors of digestion, attractants, etc., and according to their chemical composition and intensity reveal information about the physiological status of the plant and the stress in which the behavior or biology of an organism of other species; These molecules generally act in low doses and have a specific action and are not very toxic to mammals.

This second generation of botanical pesticides allowed western scientists to rediscover the neem, which was used in India since ancient times. From the seeds of the neem tree (Azadirachta indica, Meliaceae) two types of botanical pesticides can be obtained, Neem oil (essential oil) and azaridiractin (10-25%), a limonoid of the meliacin type.The limonoids have been isolated mainly from the Meliaceae (meliacinas) and Rutacea (citrus Iimonoids) families, they are chemically modified triterpenes or highly oxygenated tetranortriterpenoids, which derive from the precursor 4,4,8trimethyl-17 -furanosyl steroid. Meliacin-type limonoids are structurally more complex than citrus limonoids and have a higher degree of oxidation. Azadirachtin exerts its pesticide action by blocking the synthesis and release of hormones during molting (ecdisis) in immature insects, which results in the inhibition of their growth and development, and in adult insects through a similar mechanism, causes sterility . Azadirachtin is also a potent anti-food.

new alternatives for integrated pest management, due to the resistance developed by insects and other undesirable side effects caused by the indiscriminate use of conventional synthetic pesticides. But, on the other hand, there are also several factors that limit the use of botanical pesticides due to inconsistent practical results, probably because there is no chemical standardization of formulations; at the non-competitive price compared to classic pesticides; to inappropriate formulations and application against a limited range of pests.

Among the previous works of pesticides of plant origin related to the present invention, the patent US2005 / 0244445 was found which refers to the synergistic effect on the insecticidal activity that have formulations based on essential oils, insecticidal soaps and / or pyrethrins, with detergents such as sodium lauryl sulfate (SLS), sodium dodecyl sulfate (SDS) or lecithin.

On the other hand, in US patents US6372239 and US2008 / 0300225 the use of tetracyclocycloololidine alkaloids is described: matrine and oximatrine, isolated in Sophora roots, alone or present in a mixture of alkaloids to exert a synergistic effect on the control of pests The pesticidal activity of these alkaloids is attributed to their inhibitory effect on the enzyme acetylcholinesterase, thus inhibiting the degradation of the neurotransmitter acetylcholine. As the concentration of acetylcholine increases, hyperexcitation of the Central Nervous System (CNS) occurs, which causes the death of insects.

Additionally, Stermitz et al. (2002) reported the synergistic effect of two flavones, crisosplenetin and crisosplenol D (isolated from Artemisia annua L. extract) in the antimicrobial activity shown by berberine against Staphylococcus aureus. It was determined that these flavonoids block the extrusion of berberine from the bacterial cell, by inhibition of the multi-drug efflux pump (MDF), thus allowing it to exert its bactericidal action.

and finally, in the Chinese patent CN 2004-10022134 the manufacturing process of a pesticide is described to prevent diseases in plants caused by pathogenic microorganisms and to promote plant growth, which contains as active ingredients a mixture of 0.06 to 0.36% of Berberine hydrochloride, 0.010.06% matrine and 0.23 to 1.38% flavonoids.

pesticide with insecticidal, acaricidal and nematicidal action, novel and efficient for the integrated management of pests that attack plants, fruits and / or animals, based on a novel mixture of isoquinoline alkaloids and flavonoids from, although not exclusively, plant extracts, which show important synergistic interactions in their pesticide activity.

The isoquinoline alkaloids of the present invention may come, although not exclusively, from the Papaveraceae family and the Asteraceae flavonoids. Both types of secondary metabolites can also be chemically synthesized.

From the Papaveracea family, the presence of isoquinoline alkaloids derived from protoberberine, tetrahydroberberine, protopine and benzophenantridine and spirobenzylisoquinoline and cularine in Fumarioideae, as well as other groups that give them known pharmacological properties: aporphine, morphinan derivatives , pavina, isopavina, narceína and roeadina. At least 20 other alkaloids are known in the plants of this family: chelantifoline, queleritrin, N-norqueleritrine, dihydrokeleritrin, coptisin, cryptopin, dihydrosanguinarine, norsanguinarine, esculerin, streopine, muramine, talipoline, reframycin and oxyhydrastinine. These secondary metabolites are responsible for the medicinal properties attributed to the family.

From the Asteraceae family, specifically from the Cirsium genus, a series of compounds with pesticidal activity of different chemical nature have been isolated, including flavonoids, sterols, triterpenes, alkaloids, polyacetylenes, acetylenes, sesquiterpenes, lactones, phenolic acids and lignans. Among the flavonoids isolated from Cirsium are the glycosylated derivatives of apigenin, cirsimaritin, camferol, linarine, luteolin, pectolinarin and quercetin.

Detailed description of the invention

The present invention comprises a process for obtaining a pesticide with insecticidal, acaricidal and nematicidal action based on plant extracts, which contain as active principles: isoquinoline alkaloids and flavonoids, whose efficiency lies in presenting a synergistic effect in integrated pest management .

The alkaloids can be obtained from plants such as those of the Papaveraceae family, which can be of the genus Argemone. Alternatively, the alkaloids of the present composition can also be chemically synthesized on an industrial scale. The level of extraction and the degree of purity of the alkaloids may vary, for example, extracts of whole, unpurified plants can be used in the present invention. Depending on the solubility of the alkaloids of the plants, the process of extraction of each alkaloid can differ, being able to use water or an organic solvent. Alternatively, the alkaloids can be completely or partially purified. The chemical synthesis of alkaloids obviates the need for extraction and purification.

The formulation may contain one or more alkaloids of the isoquinolinic type and its derivatives, such as: berberine, protopine, alocriptopin, cryptopin, sanguinarine, dihydrosanguinarine, norsanguinarine, oxisanguinarine., 6-acetonyldihydrokeleritin, dihydrokeleritrine, chelerithrine, N-norketyrithine, N-norkenithyryrine, N-norkenithyryrine, N-norkenithyryrine, N-norkenithyryrine, N-norkenithyryrrine, N-norquerythryrin, N-norkenithyryrrine, N-norchetyrithine, N-norquerythryrin, N-norquerythryrin, N-norquerythryrin, N-norkenithyryrine, N-norkenithyryrin coptisin, cryptopin, esculerin, stilopine, muramine, talifoline, reframycin and oxyhydrastinine.

Flavonoids, to which the pesticide of the present invention refers, can be synthesized or obtained from various plant species of the Asteraceae family, specifically of the genus Cirsium. These flavonoids belong to the group of flavonols, flavones and isoflavones, and also comprise their glycosylated derivatives, specifically apigenin glycosides, cirsimaritin, canferol, linarine, luteolin, pectolinarin and quercetin.

All the aforementioned metabolites can be obtained through the use of biotechnological processes.

The extraction of the plant material of the present invention can be carried out, although not exclusively, by using solvents approved in the EPA list 4 or by extraction with supercritical fluids.

Obtaining the pesticide with insecticidal, acaricidal and nematicidal action of the present invention consists of two stages, in the first stage the botanical extracts are obtained and the second stage consists in mixing the extracts with the adjuvants necessary to maintain a physicochemically stable formulation .

Thus, the chemical composition of the present invention is composed of the combination or mixture of the following ingredients:

Isoquinoline alkaloids and their derivatives 0.1 -20%

Flavonoids and their glycosylated derivatives 0.001 -10%

As part of the development of the present invention, two examples of pesticide formulations are presented, which combine the active ingredients in various different pest organisms, both in the laboratory and in the field.

Example 1. Preparation process of formulate 1

Step 1. Obtaining plant extracts.

a) Process of extraction of alkaloids from Argemone spp.

To obtain the alkaloids of the plant material, the extraction method with an organic solvent is used.

For this example, the dry plant material of the Argemone spp. (Papaveraceae), is loaded into a reactor and an organic solvent is added. The extraction process was carried out within a temperature range of 30 to 70 ° C, preferably for 1-6 hours, to subsequently discharge the extract. The extract is concentrated by controlled distillation until a concentration of 0.01 to 30% is obtained. The extract is discharged and stored in a cool and dry place at a temperature of 25 ° C. The yield of alkaloids from the plant extract is about 5 to 15%.

b) Extraction of flavonoids from Cirsium spp.

Flavonoid extraction was performed analogously to the process of obtaining alkaloids described above. The dry, ground and heavy plant material of Cirsium spp. it is loaded into a reactor provided with heating and stirring, and an organic solvent is added thereto, and the mixture is stirred for a period of time preferably 1-6 h, maintaining a temperature of preferably 40 to 70 ° C. The extract obtained by this process is filtered, discharged and stored in polyethylene containers in a cool and dry place at a temperature of 25 ° C. The flavonoid yield from the plant extract is around 0.5% to 10%.

Step 2. Manufacturing process of formulate 1.

To obtain the base extract of the formulation, mixing of the active extracts of Argemone spp. and of Cirsium spp. For this, the extracts are loaded into the homogenizing reactor and preferably stirred for 1-3 h. It is discharged and the pesticide is formulated.

To carry out the formulation, the extracts, adjuvants and solvents are weighed and loaded into the homogenizing reactor in such a way that they remain in the following proportions: 0.01 to 30% of the base extract, 1-10% of adjuvants and the rest of the water . Stir the

Example 2. Preparation process of formula 2

Step 1. Preparation of plant extracts.

a) Process of extraction of alkaloids from mixing plant material.

The extraction of isoquinoline alkaloids can be done from several species of the Papaveraceae family. For this process, an appropriate amount of Argemone spp. and Bocconia sp., are placed inside a temperature controlled reactor and an organic solvent is added. The extraction is carried out at a temperature preferably from 40 to 70 ° C and stirring is continued for 1-6 hours. The extract is discharged, filtered and concentrated by distillation until a concentration of 0.01 to 30% is obtained. The extract is discharged and stored in a cool and dry place at a temperature of 25 ° C. The yield of alkaloids from the plant extract is about 5 to 15%.

b) Extraction of flavonoids from Cirsium spp. The flavonoid extraction process is the same as described for the formulation

one.

Step 2. Manufacturing process of the formulation 2.

The base extract preparation is performed. The extracts of Argemone spp., Bocconia sp. and Cirsium spp. Subsequently, the extracts are loaded into the homogenizing reactor and stirred for 1-3 h. It is discharged and the pesticide product is formulated.

For formula 2, the active extracts, adjuvants and solvents are weighed and loaded into the homogenizing reactor in such a way that they remain in the following proportions: 0.01 to 30% of the base extract and 1-10% of adjuvants and the rest of the Water. Stir for 1-3h, until a stable homogeneous solution is achieved. The formulation is unloaded and is packaged.

Examples of the evaluation of pesticide formulations:

Evaluations of two botanical formulations formulated 1 and formulated 2 were carried out, in

different crops and against different species of pest insects, the results are included

of laboratory evaluations.

The evaluation was carried out in the culture of Cucurbita pepo L., infested with insects from the

Formulated 2 5 mUL 86 Dimethoate 5 mUL

100 Water 5 mUL O

Table 111. Evaluation of the effectiveness in nymphs of Diaphorina sp. Treatment Dose% Effectiveness

In both cases the percentage of effectiveness of the samples under study was

satisfactory, it is observed that formula 2 causes a higher percentage of mortality in

Both biological states.

Table IV describes the control percentages of products for mites of the

Genus Polyphagotarsonemus. Table IV Effectiveness evaluation.

Treatment

Formulated 1

Formulated 2

Water Dose 5 mUL 5 mUL% Effectiveness

86.2

87.9

OR

Compared to the control, which presented a 0% mortality rate, the products evaluated showed a significant level of control of mites of the genus Polyphagotarsonemus in Citrus sp.

In the culture of Brassica oleracea, evaluations for larval control were carried out

of the genus Plutella, the results of this evaluation are described in table V. The

Evaluation was performed four days after application.

presented by the commercial witness. In all the evaluations carried out, it was not observed that the products developed caused any damage to the crops in which they were applied.

5 In the laboratory evaluation both products were diluted to the concentration of 5 mL of the formulated in 1 L of distilled water and applied against insects of the genus Bemisia. To compare the effectiveness of the formulation, distilled water was also applied as an absolute control and biphentrine ([1 a, 3a- (Z)] - (±) - (2methyl [1,1 '-biphenyl] -3-yl) methyl-3 - (2-Chloro-3,3,3-trifluoro-1-propenyl-2,2-dimethyl cyclopropanecarboxylate) as a commercial control.

10 formulated was performed under laboratory conditions using devices to keep specimens under observation. The effectiveness evaluation was carried out 24 hours after the application. The experimental unit consisted of four devices, which were maintained at 26 (± 2OC). Three repetitions were performed for each evaluation.

15 Table VI details the effectiveness observed for insects of the genus Bemisia at 24 hours of observation with each of the treatments. The commercial control dose (biphentrine) was the dose recommended by the manufacturer.

Table VI Evaluation of the effectiveness in vitre against insects of the genus Bemisia. Treatment Dose% Effectiveness Formulated 1 5 mUL 74.17 Formulated 2 5 mUL 74.17 Biphentrine 2 mUL 97.18 Water OR

20 The nematicidal capacity of formula 2 was evaluated, which obtained a satisfactory percentage of effectiveness at 48 h. Nematodes of the genus Me / oidogyne were used as the white organism and the results are shown in Table VII.

25 Table VII. Evaluation of the effectiveness in vitre against nematodes of the genus Me / oidogyne. Treatment Dilution% Effectiveness Formulated 2 1:10 84.29 Formulated 2 1: 100 33.93

and mentioned cultures, it is concluded that formulates 1 and 2 are suitable for the control of sucking insects (Bemisia spp.), phytophagous mites, insects of the genus Diaphorina, and phytopathogenic nematodes of the genus Meloidogyne since the observed mortality percentages are satisfactory.

Claims (14)

one.

Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids characterized in that it comprises as active ingredients at least one isoquinoline alkaloid, particularly berberine and a synergistic compound of plant origin that can be at least one glycosylated flavonoid from the group of flavonols, flavones and isoflavones, particularly pectolinarin.

2.

Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids claimed according to claim one, consisting of a composition of secondary metabolites obtained from plant extracts, characterized in that the isoquinoline alkaloid is other than berberine such as: protopin, alocriptopin, cryptopin, sanguinarine, dihydrosanguinarine, norsanguinarine, oxisanguinarine, 6-acetonyldihydrocheleritin, dihydrocheleritrine, queleritrine, Nnorqueleritrine, cheleritridimerine, cheylantipoline, coptisine, cryptopin, squin, oxydinephrine, strepinamine, oxidine, strepinamine, oxidinine, strepinamine, oxidine, strepinamine, oxidine, streptin

3.

Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids claimed according to claim one, consisting of a composition of secondary metabolites obtained from plant extracts, characterized in that the flavonoid is another different from pectolinarin, such as flavonols, flavones and isoflavones and their glycosylated derivatives, specifically to the glycosides of apigenin, cirsimaritin, caferol, linarine, luteolin and quercetin.

4. Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids, where the pesticide composition is characterized by containing: Isoquinoline alkaloids and their derivatives 0.1 -20% Flavonoids and their glycosylated derivatives 0.001 -10% 5. Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids claimed according to claim one, characterized spp. and / or Bocconia spp., although not exclusively

6.

Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids claimed according to claim one, characterized in that the pesticide flavonoids are obtained from plants of the genus Cirsium, although not exclusively.

7.

Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids claimed according to claim one, characterized in that the isoquinoline alkaloids can be the product of chemical synthesis and / or cell culture.

8.

Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids claimed according to claim one, wherein the flavonoids can be the product of chemical synthesis and / or cell culture.

9.

Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids claimed according to claim one, characterized in that its formulation contains a composition of 0.01 to 30% of the base extract and as a vehicle either water, oil or solvent.

10.

Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids claimed according to claim one, characterized in that its formulation contains one or more surfactants, humectants, dispersants and / or adherents.

eleven.

Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids claimed according to claim one, characterized in that its formulation also contains some other pesticidal component.

12.

Pesticide with insecticidal, acaricidal and nematicidal action based on isoquinoline alkaloids and flavonoids claimed according to claim one, characterized

13. Pesticide with insecticidal, acaricidal and nematicidal action based on alkaloids The isoquinoline and flavonoids claimed according to claim one, characterized in that the pesticide is used in an effective dose as a component of an urban and domestic pest control system. 14. Pesticide with insecticidal, acaricidal and nematicidal action based on alkaloids 10 isoquinoline and flavonoids claimed according to claim one, characterized in that its application form is suitable for solid type formulations such as: soaps, powders, granules, baits and encapsulates; liquid type like: emulsions, dispersions, concentrates and gel type.